1. Field of the Invention
This invention relates to an abrasive tape for use in the polishing of a magnetic head for a magnetic recording and reproducing apparatus. This invention particularly relates to an abrasive tape moved between two reels like an ordinary magnetic tape for polishing the magnetic head.
2. Description of the Prior Art
Video or high grade audio magnetic heads are required to have very smooth tape sliding surfaces. Therefore, in general, in the process of making the magnetic head, the tape sliding surface of the magnetic head is given a smooth finish by disposing the magnetic head at a predetermined position after rough grinding, and moving an abrasive tape between two reels with the magnetic head intervening therebetween. The abrasive tape comprises a nonmagnetic substrate, and fine abrasive particles, a binder, a lubricating agent or the like coated on the substrate. Since the abrasive tape is flexible, it can accurately polish the tape sliding surface of the magnetic head by snugly fitting to the curved shape thereof.
The magnetic head has heretofore been provided with a single lubricating agent as an additive for improving the sliding of the abrasive tape with respect to the magnetic head.
However, with a single lubricating agent, it is not possible to substantially achieve the lubricating effects under specific conditions. Specifically, in a high temperature atmosphere, sticking and slipping of the abrasive tape on the tape sliding surface of the magnetic head occurs even though the back tension of the abrasive tape is adjusted to a predetermined value. In this case, movement stability of the abrasive tape is lost, and it is impossible to polish the magnetic head uniformly.